During the second year of the Center for the Study of Drug Dependence our multidisciplinary approach has continued. These include joint studies carried on by clinicians and basic researchers. Faculty, staff and students from a variety of departments within the University have met for discussions of problems of mutual interest. From such discussions new research strategies and combinations of researchers have evolved. The key areas being investigated are: methadone maintenance in relationship to the preganant addict; development of immunoassay procedures for drugs of abuse; procedures for preclinical evaluation of drug abuse liability; the cytological distribution of opiate agonists and antagonists; the assessment of the physiological, behavioral and morphological consequences of chronic administration of drugs of abuse. Through our seminar series students and faculty have had the opportunity to discuss their research with leading investigators in the area of drug dependence. Such interactions have been extremely profitable. As in the first year of this grant there has been a very positive feeling on the part of the Center participants towards the collaborative research efforts which the Center has fostered.